PROFIBUS-DP从站在表格印刷机控制系统中的应用

针对印刷机外围设备分散、数据传输信息量大、实时性和可靠性要求高等问题,设计一种基于PROFIBUS-DP协议的I/O从站,用于表格印刷机的分布式控制系统.控制系统由监控计算机运行的软件PLC程序,通过PROFIBUS通信卡与现场I/O从站进行通信,形成分布式控制网络.介绍分布式控制系统的整体结构、工作原理及特点,分析PROFIBUS-DP协议,详细说明采用微控制器C8051F020和协议芯片SPC3开发I/O从站的硬件电路、软件设计流程,给出基于PRO-FIBUS现场总线的分布式控制系统网络组态与调试的方法.经系统测试和实际运行表明,I/O从站与监控计算机通信可靠、准确,实时性满足了印刷机控制系统的要求,具有一定的参考价值和广阔的应用前景.     

PROFIBUS总线与软PLC在分布式监控系统中的应用

针对印刷机外围设备多分散、实时性和可靠性要求高等问题，设计了一种基于PROFIBUS总线与软PLO的分布式监控系统。本文介绍了分布式控制系统的总体结构、I／O从站的硬件电路、软件设计流程。给出了基于软PLO与PROFIBUS现场总线的分布式控制系统的网络模型及系统组态与调试的方法。     

基于SoC的工业以太网远程I/O系统设计与实现

针对工业自动化控制系统中的远程I/O设备需要为种类繁多且互不兼容的工业以太网协议分别开发硬件设备导致开发效率低的问题,文中提出了一种利用SoC实现协议可切换的远程I/O系统。以Profinet工业以太网协议为例,使用netX 90芯片为核心实现Profinet从站功能,使用STM32微处理器实现I/O扩展功能,共同构建远程I/O系统,完成工业以太网从站对I/O的测量和控制功能。实验表明该远程I/O系统扩展性强、响应速度快、测量及控制功能稳定,可广泛应用于工业生产中的分布式测控点位。     

PROFINET在油墨生产线控制系统中的应用

该文设计了基于PROFINET油墨生产线分布式PLC控制系统。该控制系统利用新一代工业以太网技术的自动化总线标准PROFINET,以西门子S7-1513 CPU为PROFINET I/O控制器,ET 200S I/O分布式系统为PROFINET I/O设备,构建分布式油墨控制系统。通过工业以太网实现油墨生产系统网络通信和实时数据采集,保证了测量的精度,提高了数据通信的准确性与快速性。     

基于菊花链回路的工业Ethernet I/O系统改造

为解决旧式I／0系统控制层与现场层采用协议不统一导致的开放性差及中、远距离成本高等问题,将Ethernet技术延伸应用到现场级控制通信中,使现场层和控制层基于统一的Ethemet协议。在基于旧式远程I／O子站与以太网远程I／O子站的异同点分析的基础上,开展了基于菊花链回路的工业EthernetI／O系统改造和迁移过程的分析,提出了基于菊花链回路的光纤主回路和长距离热备光纤回路的的构建方法。通过Quantum通信设备,使分布式I／O主站模块、主环路上的DRSs、分布式I／O设备和远程I／O网络构成了菊花链主回路。在子回路中扫描本地分布式I／O设备,DRSs控制来自子回路的分布式I／O设备的数据流,从而保持主回路中远程I／O流量的最高优先级,通过优先级控制不同级别的I／O数据。研究结果表明,该方法既能保证网络的冗余,又能保证网络的高效和时间的确定性。     

Ethercat网络实时多任务从站设计方法研究

Ethercat是一种高速高效的主从式实时以太网技术。Ethercat从站在主站协调下完成系统底层控制任务,是典型的实时多任务处理系统,从站设计是Ethercat系统设计的难点。首先分析了Ethercat的运行原理和实时操作系统对不同类型任务的调度机制,然后探讨了一种基于通用实时操作系统的Ethercat从站设计方法。根据从站任务的实时性要求并结合Ethercat通讯协议和实时操作系统调度机制对任务进行规划与分类,使每类任务在实时操作操作系统调度下都能获得及时、有效的运行时间。最后应用该方法设计了基于实时操作系统TI/BIOS的应用于Ethercat型机器人控制系统的IO从站。     

基于Modbus／TCP的分布式I／O在列车驾驶模拟器上的应用

为了解决列车模拟器操控台上的人机接口与模拟器主机之间的实时数据传输问题,针对传统的I／O板卡体积大、成本高、维护困难等不足,提出了一种基于Modbus／TCP的分布式I/O系统解决方案。详细地介绍了Modbus／TCP协议的技术特点,开展了系统的具体性能要求分析,选取贝加莱公司的X20系统搭建了硬件平台,并以其配套的AS软件为开发平台,使用C语言编写了程序,并最终应用于上海轨道交通7号线列车模拟器上。现场运行结果表明,该系统运行稳定,实时性能符合要求、兼容性好,并能直接应用于其他线路的列车模拟器上。     

infi—90分布式控制系统软硬件配置

infi—90分布式控制系统是美国贝利控制公司推出的一种最新的计算分布式机控制系统,它有完备的硬件和功能强大的软件支持,可广泛地应用于冶金、石油、化工、纺织、电力等工业过程控制领域。软硬件配置 infi—90分布式控制系统的生成是根据不同用户的要求从硬件配置开始的,以软件组态最终完成。所谓硬件配置,就是根据系统中I/O点数和类型,选择相应的I/O子模件及多功能处理器MFP等控制器模件,并根据系统及I/O     

DCS在柠檬酸发酵过程控制中的应用

基于国产IPC和I／O模板设计了柠檬酸发酵过程微机分布式控制系统,本文介绍了该系统的软硬件结构与功能,提出了发酵过程参数的优化控制方法。     

基于PLC的70万吨高线生产自动化控制系统设计

针对70万吨高速线材自动生产线,设计了一套基于工业以太网、PROFIBUS-DP现场总线的分布式控制系统,实现了现场设备之间的信息共享,可更高效地完成控制系统的任务。整个网络系统采用HMI、PLC、工业以太网、PROFIBUS-DP现场总线及ET200M分布式I/O站的总体结构,有效地解决了由于现场设备分散、控制协调性要求高所带来的控制问题。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.